Reciprocating wedge structure including lubricant supply means

ABSTRACT

Lubrication for a fluid power actuated reciprocating wedge apparatus is carried out in a manner to protect wedging surfaces susceptible to rapid wear under exceedingly heavy load forces of as great as fifty tons or more. The wedge apparatus includes a spring-loaded wedge device, a wedge retaining structure, a driver mechanism for transmitting driving forces to the wedge device, and means for moving a lubricant of relatively heavy consistency through the wedge retaining structure. Excessive wear of wedge parts, normally taking place at a rapid rate under the heavy load forces noted in the wedging operation, is prevented by moving the lubricant into the spring-loaded wedge device as it expands and contracts so that the surfaces are always protected and a continuous exudation of small quantities of lubricant away from the wedge device is carried out to reduce wear and to exclude abrasive material from exposed slide surfaces of the wedge components.

United States Patent [191 Fletcher et a1.

[ RECIPROCATING WEDGE STRUCTURE INCLUDING LUBRICANT SUPPLY MEANS [75]Inventors: Ralph A. Fletcher, Bedford, N.l-l.;

Joseph R. Oliver, Lowell, Mass.

[52] U.S. Cl 299/22, 175/227, 299/15 [51] Int. Cl. E21c 37/04 [58] Fieldof Search 299/15, 20-23;

[56] v References Cited UNITED STATES PATENTS 3,414,328 12/1968 I Darda299/23 X Primary Examiner-Ernest R. Purser Attorney-Munroe l-l. Hamilton11,] 3,743,357 [451' July 3, 1973 15 7] ABSTRACT Lubrication for a fluidpower actuated reciprocating wedge apparatus is carried out in a mannerto protect wedging surfaces susceptible to rapid wear under exceedinglyheavy load forces of as great as fifty tons or more. The wedge apparatusincludes a spring-loaded wedge device, a wedge retaining structure, adriver mechanism for transmitting driving forces to the wedge device,and means for moving a lubricant of relatively heavy consistency throughthe wedge retaining structure. Excessive wear of wedge parts, normallytaking place at a rapid rate under the heavy load forces noted in thewedging operation, is prevented by moving the lubricant into thespring-loaded wedge device as it expands and contracts so that thesurfaces are always protected and a continuous exudation of smallquantities of lubricant away from the wedge device is carried out toreduce wear and to exclude abrasive material from exposed slide surfacesof the wedge components.

3 Claims, 8 Drawing Figures PATENTED JUL 3 i975 SHEEN? RECIPROCATINGWEDGE STRUCTURE INCLUDING LUBRICANT SUPPLY MEANS This invention relatesin general to an improved method of wedge lubrication and in particularto a lubricant bearing wedge structure of the reciprocating plug andfeather type as disclosed and claimed in U. S. Pat. No. 3,558,191 issuedJan. 26, 1971 and owned by the assignee of the present application.

In the class of-reciprocating wedge described in U.S. Pat. No.3,558,191, there is included a spring-loaded wedge device, a wedgeretaining structure and a driver mechanism for transmitting drivingforces to the wedge device. The wedge device itself is of the plug andfeather type in which a pair of wedge feathers and a centrally disposedwedge plug are designed to be located in a drilled hole in stone. Thewedge retaining structure and the driver mechanism are normallysupported externally of the drilled hole in some suitable manner. Thewedge retaining structure resiliently contains the wedge feathers in anormally contracted position against the wedge plug. A fluid pressureactuated piston arranged within thedriver mechanism is connected to thewedge plug and operates to force the wedge plug into and out of awedging position between the pair of resiliently contained wedgefeathers with side thrust forces being exerted as great as fifty tons ormore.

7 Difficulties are encountered when maintaining a reciprocating wedge ofthe fluid pressure operated type indicated in constant operation as maybe required for example in utilizing the wedge device in drilled holesin a granite quarry. Excessive wear taking place at a relatively rapidrate under side thrust forces of fifty tons or more becomes concentratedalong the inner surfaces of the wedge feathers tending to result in needfor frequent replacement of these wedge feather components. Thisreplacement operation is of a time-consuming and expensive nature. Itwill also be appreciated that wear problem becomes worse when abrasiveparticles, dust and other foreign materials, frequently present indrilled holes in stone, enter between the slide surfaces of the wedgefeathers and the wedge plug.

It is a chief object of the invention, therefore, to cope with theproblems of excessive wear in a fluid pressure operated reciprocatingwedge device, and to devise an improved method and means for lubricatingthe reciprocating wedge structure. Another more specific object is todistribute and transfer lubricant in a continuous manner which utilizesespecially the reciprocating movement of the wedge plug between thewedge feathers during each wedging operation as well as the resultantexpansion and contraction of the wedge feathers so as to maintain thinfilms of lubricant between the slide surfaces at all times.

Another object of the invention is to devise a method and means forsupplying heavy lubricant in a manner such that a continuous exudationof small quantities of lubricant is maintained through the open sides ofthe wedge device to create an outer protective mass for excludingabrasive material fromaccumulating between the wedging surfaces.

The nature of the invention and its other objects and novel featureswill be more fully understood and appreciated from the followingdescription of a preferred embodiment of the invention selected forpurposes of illustration and shown in the accompanying drawings, inwhich:

FIG. 5 is a fragmentary detail elevational view of a wedge retainingcollar construction;

FIG. 6 is a cross sectional view of the wedge'plug and wedge feathersillustrating lubricant contained therein;

FIG. 7 is a cross section taken on the line 7-7 of FIG. 3;

FIG. 8 is a detail plan view of a collar member.

FIG. 1 illustrates the wedging apparatus of the invention as it normallyappears and FIG. 2 shows in section the same wedging device in a typicalworking position in stone. As shown in FIG. 2, reference character Sdenotes a mineral mass which may consist of a block or ledge of stonesuch as granite having a vertical face F. L denotes a separation orplane of splitting along which a cleavage is desired to be carried outby means of application of wedging forces. H indicates a horizontallydrilled hole for receiving the wedge device of FIG. 1, and it will beunderstood that the hole H may be illustrative of a series of spacedapart holes for receiving a desired number of wedges as required. Itwill also be understood that vertical drilled holes may be provided asillustrated by the hole H1 in the stone 8] as shown in FIG. 7.

Considering the wedge apparatus of the invention in further detail, theparts shown generally include a selflubricating reciprocating wedgedevice, a retaining structure for resiliently supporting the wedgedevice and a driver mechanism for exerting fluid power actuated forceson the wedge device when supported in the retaining structure.

Numerals 2 and 4 (FIG. 1) denote wedge feathers which are more clearlyshown in FIG. 4 and which are designed to have centrally disposedtherebetween a wedge plug 6. The wedge plug 6 comprises a cylindricalpart which is formed at one end with a pair of beveled wedge faces 6aand 6b.

As will be noted from an inspection of FIG. 4, the wedge feathers 2 and4 comprise semicylindrical tubular sections which when placed againstone another are adapted to define a cylindrical space in which the wedgeplug 6 may be slidably received as shown in FIG. 6. At their upper ends,the wedge feathers 2 and 4 are formed with respective rectangularlyshaped flanges 2a and 4a. Opposite ends of the wedge feathers areconically shaped at 212 and 4b and extending away from the conicallyshaped ends are internal tapered liner parts 10 and 12. The parts 10 and12 have flat tapering surfaces which are complementary with the surfaces6a and 6b of wedge plug 6 and these parts vary in thickness with themaximum thickness occurring at points adjacent to the conical ends 2band 4b.

In the arrangement shown in FIGS. 4 and 6, the tapered parts 10 and 12may be secured by rivets as 14 and 16, or if desired, the twocylindrical sections 2 and dmay be formed with the tapered liner partsas integral portions of the sections. It will be apparent that thetapered surfaces of the wedge plug 6 when advanced between the wedgefeathers will engage the tapered surfaces of the liner parts and 12 andwill force the cylindrical sections 2 and 4 apart to thus exert wedgingforces in two opposite directions and substantially at right angles tothe path of travel of the wedge plug.

The wedge assembly components comprised by the members 2, 4 and 6 areresiliently supported against one another in a special retainingstructure which also houses a driver mechanism. This retaining structureincludes a housing 18 at one end of which is detachably supported acylinder 46 having a fluid power actuated driver piston 44 therein. Atan opposite end of the housing 18 is supported a wedge retaining collar20 which is mounted around the wedge plug and wedge feathers, as shownin FIGS. 1, 2, 5 and 7. Located between the collar and the drivermechanism is a cylindrical enclosure body 62 which is arranged in spacedrelation around an internally threaded plunger portion 64 of piston 44.A threaded end of the wedge plug 6 is engaged with the plunger portion64 as indicated in FIGS. 2 and 7.

The annular space occurring between the enclosure body 62 and internallythreaded plunger portion 64 operates to contain small amounts oflubricant in constant contact with the plunger and the wedge plug.

As noted in FIGS, the collar 20 is constructed with an elongated opening22 which is of size capable of receiving the wedge parts in a manner topermit the wedge feathers to move apart when the wedge plug is advancedbetween the feathers.

As shown in FIG. 3, flange portions 20 and 4a are also formed withcentrally located recesses each of which have a curvature for engagingaround and slidably supporting adjacent surfaces of the wedge plug 6when the latter member is in a fully retracted position. The curvedrecesses are formed of a size such that inner edges 2b and 2c of flange2a are at all times maintained in substantially separated relation withrespect to edges 4b and 4c of flange 4a, thereby to define a lubricantchamber which communicates with the said annular space around the member64 and which is operated to hold a further quantity of lubricant L (FIG.3). At either side of the elongated opening 22 are so]- idly fixed apair of elongated stops 24 and 26 as shown in FIGS. 3 and 8. These stopsfunction to slidably engage the side edges of the flanges 2a and 4a soas to hold them against rotative movement.

Also provided in the collar 20 are opposite radially extending openingsas 30 in which are loosely received a pair of spring-loaded pins 32 and34 which are adapted to extend through the openings 30. The inner endsof the pins 32 and 34 engage against the wedge feathers 2 and 4 assuggested in FIG. 3 and are attached to coiled springs 36 and 38 one ofwhich is more clearly shown in FIG. 8. The coiled springs are normallyheld in a compressed position by engagement with the inner peripheralsurface of the cylindrical housing 18 as shown in FIGS. 2 and 3. Thecollar 20 is also releasably held in contact with the flange portions 2aand 4a by means of a resilient lock ring 40 which is forced into agroove formed around the inner periphery of the housing as illustratedin FIGS. 2 and 3.

In accordance with the invention, we provide in combination with thestructure described lubricant inlet means M1 and M2 which are locatedthrough the collar 20 and are so arranged as to exit at points closelyadjacent to the elongated stops 24 and 26, as shown in FIG. 8, and inaddition, they occur in a position to connect with the lubricant chamberdefined by the spaced apart edges of the flanges noted above.

At an opposite side of collar 20 are lubricant fittings 20a and 20b forreceiving pressurized lubricant which may be conducted through theinlets M1 and M2, then into the lubricant chamber, and finally into theannular space around the plunger member.

In a typical wedging operation a relatively heavy lubricant isintroduced into the fittings 20a and 20b under pressure and lubricantbecomes forced into the annular space, filling this space all the wayaround the cylindrical enclosure body 64 and also completely filling thelubricant chamber between the flanges, and finally forcing lubricantinto the spaces between the wedge plug and wedge feathers. Thereafter,the wedge device is placed in a drilled hole, as illustrated in FIGS. 2and 7 with the wedge in a retracted position. The hydraulic cylinder isthen actuated to advance the wedge plug 6 between the wedge feathers andexert opposite side thrust forces which operate to separate a portion ofthe mineral body.

When the wedging operation has been completed, the wedge plug isretracted with the wedge feathers being resiliently compressed againstopposite sides of the wedge plug by means of the springs in the collar20, as described above. It will be understood that this reciprocatingmovement of the wedge plug is carried out periodically and may occurthroughout a relatively large number of splitting or wedging operations,particularly when the wedging device is used in company with a gang ofsuch members as customarily happens in using these devices in a quarrymachine.

The repeated travel of the wedge plug in and out between the wedgefeathers, being at all times in contact with lubricant in both theannular space around the wedge plug and in the lubricant chamber betweenthe flanges, results in an unique transfer of lubricant during eachreciprocation of the wedge plug. Thus when the wedge plug is advanced,the head of the wedge plug picks up lubricant and carries it downwardlyinto the spaces between the wedge feathers. A similar movement of greaseoccurs from the lubricant chamber into the space between the wedgefeathers. However, when the wedge plug is retracted, since the wedgefeathers are resiliently contained against opposite sides of the wedgeplug, some of the lubricant is extruded from the opposite spaces betweenthe wedge feathers, while still other portions of the lubricant arecompressed and displaced upwardly through the lubricant chamber. As thismovement of lubricant takes place while the flanges are moving towardand away from one another, they and their surfaces are constantlyprotected with a thin film of lubricant as well as the slide surfaces ofthe wedge plug and the wedge feathers. The action of the wedge feathersin compressing lubricant contained between themselves and the wedge plugnecessarily forces a'small amount of the lubricant outwardly so that aprotective mass is present all along the outer edges of the wedgefeathers, and thus no grit, dust or other foreign material can enter tocause excessive wear.

It is also pointed out that by arranging the lubricant fittings in theparticular manner shown and described by applicant, a periodicreplacement of lubricant may be readily accomplished without removingthe wedge device from the supporting structure in which it may becontained.

We claim:

1. A reciprocating wedge apparatus for use in a drilled hole, said wedgeapparatus including a fluid pressure actuated driver mechanism having aplunger element, a wedge plug secured at one end of the plunger element,a cylindrical enclosure body located around the plunger in spacedrelation thereto to define an annular space, a pair of wedge feathersslidably disposed at opposite sides of the wedge plug, said wedgefeathers having transversely extending flange portions arranged inabutting relation against one end of the cylindrical enclosure body andbeing spaced apart to provide .a lubricant chamber communicating withthe annular space, a wedge retaining collar located around the wedgefeathers, said collar being formed with an elliptically shaped openingin which the wedge feathers are resiliently contained and guided fortransverse expansion and contraction when the plunger and wedge plug arereciprocated, said collar being formed with lubricant conductingfittings and connecting passageways which exit at the said lubricantchamber at points between the said flanged portions and in spacedrelation to the said elliptically shaped opening at opposite sidesthereof.

2. A self-lubricating reciprocating wedge device comprising incombination a fluid pressure operated driver mechanism, a plungerelement supported for reciprocating movement at one end of the drivermechanism, a wedge plug secured to the plunger, a cylindrical enclosurebody located around the plunger to define an annular space, a pair oftransversely movable wedge feathers arranged to slidably receive thewedge plug therebetween, said wedge feathers having transverselyextending flange portions arranged in abutting relation against an endof the enclosure body and being spaced apart to define a lubricantretaining chamber which communicates with the annular space, a wedgeretaining collar located around the wedge plug and wedge feathers andbeing constructed with an elongated slot in which the wedge feathers aretransversely displaceable when the wedge plug is advanced therebetween,a pair of parallel spaced apart stops fixed at one side of the collarfor guiding transverse displacement of the flanges, spring loaded pinmeans projecting radially inwardly of the collar in a position toresiliently engage against each of the said wedge feathers and yieldablyhold the wedge feathers against the wedge plug, said collar constructedwith lubricant injecting inlet means which exit at an inner side ofthecollar at points between the said flanged portions to formpassageways connecting with the lubricant retaining chamber, andlubricant fittings mounted at an outer side of the collar and connectedto the said lubricant injecting inlet means for receiving and conductingpressurized lubricant into the lubricant chamber and the said annularspace.

3. A self-lubricating reciprocating wedge device comprising incombination a fluid pressure operated driver mechanism, a plungerelement supported for reciprocating movement at one end of the drivermechanism, a wedge plug secured to the plunger, a cylindrical enclosurebody located around the plunger in spaced relation to define an annularspace, a pair of transversely movable wedge feathers arranged toslidably receive the wedge plug therebetween, said wedge feathers beingformed with flanged portions slidably abutting against an end of theenclosure body and being spaced apart to .form a lubricant retainingchamber, a wedge retaining collar located around the wedge plug andwedge feathers and being constructed with an elongated slot in which thewedge feathers are transversely displaceable when the wedge plug isadvanced therebetween, a pair of parallel spaced apart stops fixed atone side of the collar for guiding transverse displacement of theflanges, spring loaded pin means projecting radially inwardly of thecollar in a position to resiliently engage against each of the saidwedge feathers and yieldably hold the wedge feathers against the wedgeplug, said collar constructed with lubricant of relatively heavyconsistency contained in the annular space in contact injecting inletmeans which exit at an inner side of the collar at points between thesaid flanged portions, a body of lubricant of relatively heavyconsistency contained in the annular space in contact with the saidplunger and connected wedge plug portion, said body of lubricantextending into the lubricant chamber between the wedge feather flangesin a position to be periodically compressed and extruded from betweenthe wedge feathers as they are moved toward and away from one anotherwhen the wedge plug is being recip-

1. A reciprocating wedge apparatus for use in a drilled hole, said wedgeapparatus including a fluid pressure actuated driver mechanism having aplunger element, a wedge plug secured at one end of the plunger element,a cylindrical enclosure body located around the plunger in spacedrelation thereto to define an annular space, a pair of wedge feathersslidably disposed at opposite sides of the wedge plug, said wedgefeathers having transversely extending flange portions arranged inabutting relation against one end of the cylindrical enclosure body andbeing spaced apart to provide a lubricant chamber communicating with theannular space, a wedge retaining collar located around the wedgefeathers, said collar being formed with an elliptically shaped openingin which the wedge feathErs are resiliently contained and guided fortransverse expansion and contraction when the plunger and wedge plug arereciprocated, said collar being formed with lubricant conductingfittings and connecting passageways which exit at the said lubricantchamber at points between the said flanged portions and in spacedrelation to the said elliptically shaped opening at opposite sidesthereof.
 2. A self-lubricating reciprocating wedge device comprising incombination a fluid pressure operated driver mechanism, a plungerelement supported for reciprocating movement at one end of the drivermechanism, a wedge plug secured to the plunger, a cylindrical enclosurebody located around the plunger to define an annular space, a pair oftransversely movable wedge feathers arranged to slidably receive thewedge plug therebetween, said wedge feathers having transverselyextending flange portions arranged in abutting relation against an endof the enclosure body and being spaced apart to define a lubricantretaining chamber which communicates with the annular space, a wedgeretaining collar located around the wedge plug and wedge feathers andbeing constructed with an elongated slot in which the wedge feathers aretransversely displaceable when the wedge plug is advanced therebetween,a pair of parallel spaced apart stops fixed at one side of the collarfor guiding transverse displacement of the flanges, spring loaded pinmeans projecting radially inwardly of the collar in a position toresiliently engage against each of the said wedge feathers and yieldablyhold the wedge feathers against the wedge plug, said collar constructedwith lubricant injecting inlet means which exit at an inner side of thecollar at points between the said flanged portions to form passagewaysconnecting with the lubricant retaining chamber, and lubricant fittingsmounted at an outer side of the collar and connected to the saidlubricant injecting inlet means for receiving and conducting pressurizedlubricant into the lubricant chamber and the said annular space.
 3. Aself-lubricating reciprocating wedge device comprising in combination afluid pressure operated driver mechanism, a plunger element supportedfor reciprocating movement at one end of the driver mechanism, a wedgeplug secured to the plunger, a cylindrical enclosure body located aroundthe plunger in spaced relation to define an annular space, a pair oftransversely movable wedge feathers arranged to slidably receive thewedge plug therebetween, said wedge feathers being formed with flangedportions slidably abutting against an end of the enclosure body andbeing spaced apart to form a lubricant retaining chamber, a wedgeretaining collar located around the wedge plug and wedge feathers andbeing constructed with an elongated slot in which the wedge feathers aretransversely displaceable when the wedge plug is advanced therebetween,a pair of parallel spaced apart stops fixed at one side of the collarfor guiding transverse displacement of the flanges, spring loaded pinmeans projecting radially inwardly of the collar in a position toresiliently engage against each of the said wedge feathers and yieldablyhold the wedge feathers against the wedge plug, said collar constructedwith lubricant injecting inlet means which exit at an inner side of thecollar at points between the said flanged portions, a body of lubricantof relatively heavy consistency contained in the annular space incontact with the said plunger and connected wedge plug portion, saidbody of lubricant extending into the lubricant chamber between the wedgefeather flanges in a position to be periodically compressed and extrudedfrom between the wedge feathers as they are moved toward and away fromone another when the wedge plug is being reciprocated.